First Report of Mucor Rot on Stored ‘Gala’ Apple Fruit Caused by Mucor piriformis in Pennsylvania

Mucor piriformis E. Fischer causes Mucor rot of pome and stone fruits during storage and has been reported in Australia, Canada, Germany, Northern Ireland, South Africa, and portions of the United States (1,2). Currently, there is no fungicide in the United States labeled to control this wound pathogen on apple. Cultural practices of orchard sanitation, placing dry fruit in storage, and chlorine treatment of dump tanks and flumes are critical for decay management (3,4). Cultivars like ‘Gala’ that are prone to cracking are particularly vulnerable as the openings provide ingress for the fungus. Mucor rot was observed in February 2013 at a commercial packing facility in Pennsylvania. Decay incidence was ~15% on ‘Gala’ apples from bins removed directly from controlled atmosphere storage. Rot was evident mainly at the stem end and was light brown, watery, soft, and covered with fuzzy mycelia. Salt-and-pepper colored sporangiophores bearing terminal sporangiospores protruded through the skin. Five infected apple fruit were collected, placed in an 80-count apple box on trays, and temporarily stored at 4°C. Isolates were obtained aseptically from decayed tissue, placed on potato dextrose agar (PDA) petri plates, and incubated at 25°C with natural light. Five single sporangiospore isolates were identified as Mucor piriformis based on cultural characteristics according to Michailides and Spotts (1). The isolates produced columellate sporangia attached terminally on short and tall, branched and unbranched sporangiophores. Sporangiospores were ellipsoidal, subspherical, and smooth. Chlamydospore-like resting structures (gemmae), isogametangia, and zygospores were not evident in culture. Mycelial growth was examined on PDA, apple agar (AA), and V8 agar (V8) at 25°C with natural light. Isolates grew best on PDA at rates that ranged from 38.4 ± 5.3 to 34.5 ± 2.41 mm/day, followed by AA from 30.5 ± 1.22 to 28.5 ± 2.51 mm/day, and V8 from 29.2 ± 3.0 to 26.7 ± 2.17 mm/day. Species-level identification was conducted by isolating genomic DNA, amplifying a portion of the 28S rDNA gene, and directly sequencing the products. MegaBLAST analysis of the 2X consensus sequences revealed that all five isolates were 99% identical to M. piriformis (GenBank Accession No. JN2064761) with E values of 0.0, which confirms the morphological identification. Koch's postulates were conducted using organic ‘Gala’ apples that were surface sanitized with soap and water, then sprayed with 70% ethanol and allowed to air dry. Wounds 3 mm deep were created using the point of a finishing nail and then inoculated with 50 μl of a sporangiospore suspension (1 × 105 sporangiospores/ml) for each isolate. Ten fruit were inoculated with each isolate, and the experiment was repeated. The fruit were stored at 25°C in 80-count boxes on paper trays for 14 days. Decay observed on inoculated ‘Gala’ fruit was similar to symptoms originally observed on ‘Gala’ apples from storage and the pathogen was re-isolated from inoculated fruit. This is the first report of M. piriformis causing postharvest decay on stored apples in Pennsylvania and reinforces the need for the development of additional tools to manage this economically important pathogen. References: (1) T. J. Michailides, and R. A. Spotts. Plant Dis. 74:537, 1990. (2) P. L. Sholberg and T. J. Michailides. Plant Dis. 81:550, 1997. (3) W. L. Smith et al. Phytopathology 69:865, 1979. (4) R. A. Spotts. Compendium of Apple and Pear Diseases and Pests: Second Edition. APS Press, St. Paul, MN, 2014.

Download Full-text

First Report of Colletotrichum fioriniae Causing Postharvest Decay on ‘Nittany’ Apple Fruit in the United States

Plant Disease ◽

10.1094/pdis-08-13-0816-pdn ◽

2014 ◽

Vol 98 (7) ◽

pp. 993-993 ◽

Cited By ~ 14

Author(s):

L. P. Kou ◽

V. Gaskins ◽

Y. G. Luo ◽

W. M. Jurick

Keyword(s):

United States ◽

Cold Storage ◽

Management Practices ◽

The United States ◽

Apple Fruit ◽

Morphological Identification ◽

Conidial Suspension ◽

First Report ◽

Postharvest Decay ◽

Bitter Rot

Bitter rot of apple is caused by Colletotrichum acutatum and C. gleosporioides and is an economically important disease in the mid-Atlantic and southern regions of the United States (1). However, other Colletotrichum spp. have been found to infect apple and pear fruit in Croatia that include C. fioriniae and C. clavatum (3). The disease is favorable under wet, humid conditions and can occur in the field or during storage causing postharvest decay (2). In February 2013, ‘Nittany’ apples with round, brown, dry, firm lesions having acervuli in concentric rings were observed at a commercial cold storage facility in Pennsylvania. Samples were placed on a paper tray in an 80-count apple box and immediately transported to the lab. Fruit were rinsed with sterile water, and lesions were sprayed with 70% ethanol until runoff. The skin was aseptically removed with a scalpel, and tissue under the lesion was placed onto potato dextrose agar (PDA) petri dishes. Dishes were incubated at 25°C with constant light, and a single-spore isolate was propagated on PDA. Permanent cultures were maintained as PDA slants stored at 4°C in darkness. The isolate was identified as a Colletotrichum sp. based on culture morphology, having light gray mycelium with a pinkish reverse and abundant pin-shaped melanized acervuli oozing pink conidia on PDA. Conidia were fusiform, pointed at one or both ends, one-celled, thin-walled, aseptate, hyaline, and averaged 10.5 μm (7.5 to 20 μm) long and 5.1 μm (5 to 10 μm) wide (n = 50). Genomic DNA was extracted from mycelia and amplified using conventional PCR and gene specific primers for 313 bp of the Histone 3 gene and with ITS4/5 primers for the internal transcribed spacer (ITS) rDNA region. MegaBLAST analysis of both gene sequences showed that our isolate was identical to other Colletotrichum fioriniae sequences in GenBank and was 100% identical to culture-collection C. fioriniae isolate CBS:128517, thus confirming the morphological identification. To prove pathogenicity, Koch's postulates were conducted using organic ‘Gala’ apple fruit that were washed with soap and water, sprayed with 70% ethanol, and wiped dry. The fruit were wounded with a sterile nail to a 3-mm depth, inoculated with 50 μl of a conidial suspension (1 × 104 conidia/ml), and stored at 25°C in 80-count boxes on paper trays for 14 days. Lesion diameter was measured from 10 replicate fruit with a digital micrometer and averaged 31.2 mm (±2.5 mm) over two experiments (n = 20). Water-only controls were symptomless. Artificially inoculated ‘Gala’ apples had identical external and internal symptoms (v-shaped decay pattern when the fruit were cut in half) to those observed on ‘Nittany’ apples that were originally obtained from cold storage. Bitter rot caused by C. fioriniae may become an emerging problem for the pome fruit growing industry in the near future, and may require investigation of new disease management practices to control this fungus. This is the first report of postharvest decay caused by C. fioriniae on apple fruit from cold storage in the United States. References: (1) H. W. Anderson. Diseases of Fruit Crops. McGraw-Hill, New York, 1956. (2) A. R. Biggs et al. Plant Dis. 85:657, 2001. (3) D. Ivic et al. J. Phytopathol. 161:284, 2013.

Download Full-text

First Report of Alternaria tenuissima Causing Postharvest Decay on Apple Fruit from Cold Storage in the United States

Plant Disease ◽

10.1094/pdis-07-13-0802-pdn ◽

2014 ◽

Vol 98 (5) ◽

pp. 690-690 ◽

Cited By ~ 1

Author(s):

L. P. Kou ◽

V. L. Gaskins ◽

Y. G. Luo ◽

W. M. Jurick

Keyword(s):

United States ◽

South Africa ◽

Cold Storage ◽

Fungal Pathogens ◽

The United States ◽

Apple Fruit ◽

Conidial Suspension ◽

Single Spore ◽

Alternaria Tenuissima ◽

First Report

Apples are grown and stored for 9 to 12 months under controlled atmosphere conditions in the United States. During storage, apples are susceptible to various fungal pathogens, including several Alternaria species (2). Alternaria tenuissima (Nees) Wiltshire causes dry core rot (DCR) on apples during storage and has recently occurred in South Africa (1). Losses range widely, but typically occur at 6 to 8% annually due to this disease (2). In February 2013, ‘Nittany’ apples with round, dark-colored, dry, spongy lesions were obtained from wooden bins in a commercial cold storage facility located in Pennsylvania. Symptomatic fruits were transported to the lab, rinsed with sterile water, and the lesions were sprayed with 70% ethanol until runoff and wiped dry. The skin was aseptically removed with a scalpel, and asymptomatic tissue was placed onto potato dextrose agar (PDA) and incubated at 25°C. Two single-spore isolates were propagated on PDA and permanent cultures were maintained as slants and stored at 4°C. The fungus produced a cottony white mycelium that turned olive-green to brown with abundant aerial hyphae and had a dark brown to black reverse on PDA. Isolates were identified as Alternaria based on conidial morphology as the spores were slightly melanized and obclavate to obpyriform catentulate with longitudinal and transverse septa attached in unbranched chains on simple short conidiophores. Conidia ranged from 10 to 70 μm long (mean 27.7 μm) and 5 to 15 μm wide (mean 5.25 μm) (n = 50) with 1 to 6 transverse and 0 to 2 longitudinal septa. Conidial beaks, when present, were short (5 μm or less) and tapered. Mycelial genomic DNA was extracted, and a portion of the histone gene (357 bp) was amplified via gene specific primers (Alt-His3-F/R) using conventional PCR (Jurick II, unpublished). The forward and reverse sequences were assembled into a consensus representing 2× coverage and MegaBLAST analysis showed that both isolates were 100% identical to Alternaria tenuissima isolates including CR27 (GenBank Accession No. AF404622.1) that caused DCR on apple fruit during storage in South Africa. Koch's postulates were conducted using 10 organic ‘Gala’ apple fruit that were surface sterilized with soap and water, sprayed with 70% ethanol, and wiped dry. The fruit were aseptically wounded with a nail to a 3 mm depth, inoculated with 50 μl of a conidial suspension (1 × 104 conidia/ml), and stored at 25°C in 80 count boxes on paper trays for 21 days. Mean lesion diameters on inoculated ‘Gala’ apple fruit were 19.1 mm (±7.4), water only controls (n = 10 fruit) were symptomless, and the experiment was repeated. Symptoms observed on artificially inoculated ‘Gala’ apple fruit were similar to the decay observed on ‘Nittany’ apples from cold storage. Based on our findings, it is possible that A. tenuissima can cause decay that originates from wounded tissue in addition to dry core rot, which has been reported (1). Since A. tenuissima produces potent mycotoxins, even low levels of the pathogen could pose a health problem for contaminated fruit destined for processing and may impact export to other countries. To the best of our knowledge, this is the first report of alternaria rot caused by A. tenuissima on apple fruit from cold storage in the United States. References: (1) J. C. Combrink et al. Decid. Fruit Grow. 34:88, 1984. (2) M. Serdani et al. Mycol. Res. 106:562, 2002. (3) E. E. Stinson et al. J. Agric. Food Chem. 28:960, 1980.

Download Full-text

First Report of Cytospora punicae Causing Wood Canker and Branch Dieback of Pomegranate (Punica granatum) in the United States

Plant Disease ◽

10.1094/pdis-11-13-1133-pdn ◽

2014 ◽

Vol 98 (6) ◽

pp. 853-853 ◽

Cited By ~ 5

Author(s):

F. Peduto Hand ◽

R. A. Choudhury ◽

W. D. Gubler

Keyword(s):

United States ◽

Elongation Factor ◽

Punica Granatum ◽

The United States ◽

Internal Transcribed Spacer Region ◽

Intermittent Light ◽

First Report ◽

Consensus Sequences ◽

Vascular Discoloration ◽

Branch Dieback

Pomegranates (Punica granatum L.) are an expanding industry in the United States with California growing approximately 32,000 acres with a crop value of over $155 million (1). During June and July of 2012, we observed severe limb and branch dieback in pomegranate orchards cv. Wonderful located in Contra Costa, Kings, and Kern counties of California. Disease symptoms included yellowing of leaves, branch and limb dieback, wood lesions, and canker formation. Dark brown Cytospora-like cultures were consistently isolated from active cankers on potato dextrose agar (PDA) amended with 100 mg l−1 tetracycline hydrochloride. Three isolates (UCCE1223, UCCE1233, and UCCE1234) representative of each orchard were sub-cultured onto PDA and incubated at 22°C under fluorescent intermittent light (12 h light, 12 h dark). Fungal colonies had whitish mycelia that turned olive green to dark brown with maturity and formed globose and dark brown pycnidia after 12 days. Conidia were hyaline, aseptate, allantoid, and (4) 4.5 to 5 (6) × (1) 1.5 (2) μm (n = 180). Pycnidia formed in culture measured (250) 350 to 475 (650) μm in diameter (n = 40). Identification of the isolates was confirmed by sequence comparison of the internal transcribed spacer region (ITS1-5.8S-ITS2) of the rDNA and part of the translation elongation factor 1-α gene (EF1-α) with sequences available in GenBank. Consensus sequences of both genes of all isolates showed 99% homology to the species Cytospora punicae Sacc. (2). All sequences were deposited in GenBank (Accession Nos. KJ621684 to 89). Pathogenicity of the isolates was determined by branch inoculation. In December 2012, 3-year-old branches of P. granatum cv. Wonderful were inoculated by placing 5-mm-diameter mycelium plugs from the growing margin of 14-day-old PDA cultures in fresh wounds made with a 5-mm-diameter cork-borer. Eight branches per isolate were inoculated on eight different trees. Eight control branches were inoculated with non-colonized PDA agar plugs. Inoculations were covered with Vaseline and wrapped with Parafilm to retain moisture. Branches were harvested in August 2013 and examined for canker development and the extent of vascular discoloration spreading downward and upward from the inoculation point. Isolations from the edge of discolored tissue were conducted to fulfill Koch's postulates. C. punicae was re-isolated from 100% of the inoculated branches. Total length of vascular discoloration averaged 30.2 mm in branches inoculated with the three C. punicae isolates and 9 mm in the control branches. No fungi were isolated from the slightly discolored tissue of the controls. To our knowledge, this is the first report of C. punicae as a fungal trunk pathogen of pomegranate trees in the United States. References: (1) California County Agricultural Commissioners' Data, 2010 Crop Year. USDA NASS California field office, retrieved from http://www.nass.usda.gov/Statistics_by_State/California/ Publications/AgComm/201010cactb00.pdf , 2011. (2) P. A. Saccardo. Sylloge Fungorum 3:256, 1884.

Download Full-text

First Report of Penicillium griseofulvum Causing Blue Mold on Stored Apples in Italy (Piedmont)

Plant Disease ◽

10.1094/pdis-08-10-0568 ◽

2011 ◽

Vol 95 (1) ◽

pp. 76-76 ◽

Cited By ~ 3

Author(s):

D. Spadaro ◽

A. Lorè ◽

M. T. Amatulli ◽

A. Garibaldi ◽

M. L. Gullino

Keyword(s):

High Performance ◽

The United States ◽

Apple Fruit ◽

Morphological Identification ◽

Blue Mold ◽

Sequence Coverage ◽

First Report ◽

Golden Delicious ◽

Penicillium Griseofulvum ◽

Piedmont Region

In northern Italy, blue mold can occur generally on apples after 3 months of storage under controlled atmospheres. The mold can be caused by Penicillium griseofulvum Dierckx (synonym P. urticae Bainier). During 2008, several postharvest fruit rots were observed on apples (cv. Golden Delicious) after 180 to 240 days of storage at 1°C. Approximately 8% of the fruits showed blue mold. Apples had been cultivated in Aosta (Aosta Valley Region) and Lagnasco (Piedmont Region). Infected fruits showed soft, watery, brown spots enlarging rapidly at 20°C. There was a distinct margin between soft rotted flesh and firm healthy tissues. Under high humidity, masses of blue-green spores formed on the surface of the lesion. Apple fruit excisions from the margin between the healthy and diseased tissues were plated on potato dextrose agar (PDA), pH 5.6. The recovered fungus produced abundant mycelium and conidia, with the colonies attaining a diameter of 2.0 to 2.4 cm after 7 days at 20 ± 2°C on PDA. Colonies were mostly yellow-green, with a yellowish-to-orange brown underside. Conidiophores were mononematous or loosely synnematous, hyaline, with branches strongly divergent. Phialides were cylindrical with a very short neck. Conidia were ellipsoidal, sometimes subglobose, 2.5 to 3.5 × 2.2 to 2.5 μm, hyaline to greenish. Preliminary morphological identification of the fungus (2) was confirmed by PCR using genomic DNA extracted from mycelia of pure cultures. Two sequences, obtained through the amplification of ribosomal region ITS1-5.8S-ITS2 (1), were blast searched in GenBank and showed 99% sequence coverage and 99% similarity to ribosomal sequences of P. griseofulvum. Two sequences were deposited in GenBank with Accession Nos. HQ012498 (a strain from Aosta Valley) and HQ012499 (a strain from the Piedmont Region). Pathogenicity was tested on 20 ripe fruits each of four apple cultivars (Golden Delicious, Red Chief, Granny Smith, and Royal Gala). Fruits were surface sterilized with 1% sodium hypochlorite. Conidial suspensions (30 μl of 105 conidia/ml) of the fungus were placed on artificial wounds generated on the apple surface. Control fruits were treated with sterile water. Seven days after inoculation, the symptoms were reproduced on the four cultivars and P. griseofulvum was reisolated on PDA from the inoculated fruits of all four cultivars. Control fruits were symptomless. An analysis using high-performance liquid chromatography with diode array of the rotting tissues associated with inoculated fruits of all four cultivars (4) confirmed, as in the case of other strains of P. griseofulvum, the production of the mycotoxin patulin (12.1 to 44.4 mg kg–1). Previously, P. griseofulvum was reported on apple in other countries such as the United States (3), Japan, Egypt, and Brazil. To our knowledge, this is the first report of P. griseofulvum on apples during storage in Italy. References: (1) R. Nilsson et al. FEMS Microbiol. Lett. 296:97, 2009. (2) R. A. Samson and J. L. Pitt. Integration of Modern Taxonomic Methods for Penicillium and Aspergillus Classification. Harwood Academic Publishers, Singapore, 2001. (3) P. G. Sanderson and R. A. Spotts. Phytopathology 85:103, 1995. (4) D. Spadaro et al. Food Addit. Contam. B 1:134, 2008.

Download Full-text

First Report of Five Sooty Blotch and Flyspeck Fungi on Prunus americana in the United States

Plant Disease ◽

10.1094/pdis-91-12-1685b ◽

2007 ◽

Vol 91 (12) ◽

pp. 1685-1685 ◽

Cited By ~ 5

Author(s):

J. Latinović ◽

J. C. Batzer ◽

K. B. Duttweiler ◽

M. L. Gleason ◽

G. Sun

Keyword(s):

United States ◽

The United States ◽

Apple Fruit ◽

Economic Losses ◽

Research Station ◽

First Report ◽

Sooty Blotch ◽

Sooty Blotch And Flyspeck ◽

Pcr Products ◽

Pure Cultures

The sooty blotch and flyspeck (SBFS) complex includes more than 30 fungi that blemish the cuticle of apple fruit, causing economic losses in humid regions worldwide (1). In August 2005, we sampled SBFS-infested wild plum (Prunus americana) fruit growing in hedgerows in Iowa. Colonies were categorized according to mycelial type (1), and isolates were made from representative colonies onto acidified water agar (AWA). Plum skins with SBFS signs were excised, pressed, and photographed. DNA was obtained from purified isolates and also from mycelium and fruiting bodies scraped directly from plum fruit skins. Extracted DNA was amplified using primer pair ITS1-F/Myc1-R (ACTCGTCGAAGGAGCTACG) and PCR products were sequenced using primer pair ITS-1F/ITS4. Six sequences were obtained from pure cultures and seven from colonies on plum fruit skin. BLAST analysis of the 470-bp sequences showed 100% homology to five known species in the SBFS complex: Zygophiala cryptogama, Zygophiala wisconsinensis, Pseudocercosporella sp. RH1, and Stomiopeltis spp. RS1 and RS2 (GenBank Accession Nos. AY598854, AY598853, AY5988645, AY598882, and AY598883, respectively). Observations of colony and fruiting structure morphology from cultures on potato dextrose agar (PDA) and colonies on plums confirmed species identity. A modified version of Koch's postulates was conducted to verify that these fungi caused the signs observed on plum and could also infest apple fruit. In June 2006, 1-month-old cultures on PDA were pulverized in a blender with sterile distilled water, passed through four layers of sterile cheesecloth, and transferred to sterile jars. Each isolate was inoculated onto 20 fruit on plum trees (P. americana) on the Iowa State University (ISU) campus and 20 fruit on cv. Golden Delicious apple trees at the ISU Research Station, Gilbert, IA. Each fruit was disinfested with 70% ethanol, air dried, swabbed with inoculum, and covered with a Fuji bag. At harvest, fungal colonies on fruit were reisolated onto AWA. DNA was extracted from pure cultures; when isolations on agar were unsuccessful, DNA was extracted directly from colonies on fruit. PCR was conducted using ITS1-F/Myc1-R, and PCR products were sequenced using ITS1-F/ITS4. All five species were reisolated and sequenced from apple. Pseudocercosporella sp. RH1 and Stomiopeltis sp. RS1 were sequenced from inoculated plums. Although flyspeck, presumably caused by Schizothyrium pomi, was reported on Japanese plum (P. salicina) in Japan (2) and black cherry (P. serotina) in the United States (3), to our knowledge this is the first report of SBFS fungi on plum in the United States and the first confirmation that fungi from plum can produce SBFS signs on apple fruit. Wild plum may therefore act as a reservoir host, providing inoculum for SBFS infestations on apple. References: (1) J. Batzer et al. Mycologia 97:1268, 2005. (2) H. Nasu and H. Kunoh. Plant Dis. 71:361, 1987. (3) T. B. Sutton. Plant Dis. 72:801, 1988.

Download Full-text

First Report of Penicillium expansum Isolates Resistant to Pyrimethanil from Stored Apple Fruit in Pennsylvania

Plant Disease ◽

10.1094/pdis-12-13-1214-pdn ◽

2014 ◽

Vol 98 (7) ◽

pp. 1004-1004 ◽

Cited By ~ 4

Author(s):

H. J. Yan ◽

V. L. Gaskins ◽

I. Vico ◽

Y. G. Luo ◽

W. M. Jurick

Keyword(s):

United States ◽

The United States ◽

Apple Fruit ◽

Washington State ◽

Penicillium Expansum ◽

Economic Losses ◽

Conidial Suspension ◽

Blue Mold ◽

First Report ◽

Penicillium Spp

Apples in the United States are stored in low-temperature controlled atmospheres for 9 to 12 months and are highly susceptible to blue mold decay. Penicillium spp. cause significant economic losses worldwide and produce mycotoxins that contaminate processed apple products. Blue mold is managed by a combination of cultural practices and the application of fungicides. In 2004, a new postharvest fungicide, pyrimethanil (Penbotec 400 SC, Janseen PMP, Beerse, Belgium) was registered for use in the United States to control blue mold on pome fruits (1). In this study, 10 blue mold symptomatic ‘Red Delicious’ apples were collected in May 2011 from wooden bins at a commercial facility located in Pennsylvania. These fruit had been treated with Penbotec prior to controlled atmosphere storage. Ten single-spore Penicillium spp. isolates were analyzed for growth using 96-well microtiter plates containing Richards minimal medium amended with a range of technical grade pyrimethanil from 0 to 500 μg/ml. Conidial suspensions adjusted to 1 × 105 conidia/ml were added to three 96-well plates for each experiment; all experiments were repeated three times. Nine resistant isolates had prolific mycelial growth at 500 μg/ml, which is 1,000 times the discriminatory dose that inhibited baseline sensitive P. expansum isolates from Washington State (1). However, one isolate (R13) had limited conidial germination and no mycelial proliferation at 0.5 μg/ml and was categorized as sensitive. One resistant (R22) and one sensitive (R13) isolate were selected on the basis of their different sensitivities to pyrimethanil. Both isolates were identified as P. expansum via conventional PCR using β-tubulin gene-specific primers according to Sholberg et al. (2). Analysis of the 2X consensus amplicon sequences from R13 and R22 matched perfectly (100% identity and 0.0 E value) with other P. expansum accessions in GenBank including JN872743.1, which was isolated from decayed apple fruit from Washington State. To determine if pyrimethanil applied at the labeled rate of 500 μg/ml would control R13 or R22 in vivo, organic ‘Gala’ apple fruit were wounded, inoculated with 50 μl of a conidial suspension (1 × 104 conidia/ml) of either isolate, dipped in Penbotec fungicide or sterile water, and stored at 25°C for 7 days. Twenty fruit composed a replicate within a treatment and the experiment was performed twice. Non-inoculated water-only controls were symptomless, while water-dipped inoculated fruit had 100% decay with mean lesion diameters of 36.8 ± 2.68 mm for R22 and 38.5 ± 2.61 mm for R13. The R22 isolate caused 30% decay with 21.6 ± 5.44 mm lesions when inoculated onto Penbotec-treated apples, while the R13 isolate had 7.5% decay incidence with mean lesion diameters of 23.1 ± 3.41 mm. The results from this study demonstrate that P. expansum pyrimethanil-resistant strains are virulent on Penbotec-treated apple fruit and have the potential to manifest in decay during storage. To the best of our knowledge, this is the first report of pyrimethanil resistance in P. expansum from Pennsylvania, a major apple growing region for the United States. Moreover, these results illuminate the need to develop additional chemical, cultural, and biological methods to control this fungus. References: (1) H. X. Li and C. L. Xiao. Phytopathology 98:427, 2008. (2) P. L. Sholberg et al. Postharvest Biol. Technol. 36:41, 2005.

Download Full-text

First Report of Fusarium avenaceum Causing Postharvest Decay of ‘Gala’ Apple Fruit in the United States

Plant Disease ◽

10.1094/pdis-07-13-0803-pdn ◽

2014 ◽

Vol 98 (5) ◽

pp. 690-690

Author(s):

L. P. Kou ◽

V. L. Gaskins ◽

Y. G. Luo ◽

W. M. Jurick

Keyword(s):

United States ◽

Cold Storage ◽

The United States ◽

Apple Fruit ◽

Fusarium Avenaceum ◽

Primary Concern ◽

Processing Industry ◽

First Report ◽

Postharvest Decay ◽

Fusarium Rot

Apples are kept in controlled atmosphere cold storage for 9 to 12 months and are highly susceptible to postharvest decay caused by various fungi. Fusarium avenaceum is a wound pathogen that has been shown to account for the majority of Fusarium rot on apple fruit in Croatia (1). F. avenaceum produces an array of mycotoxins including moniliformin, acuminatopyrone, and chrysogine, which are of primary concern for the apple processing industry (2). In February 2013, ‘Gala’ apple fruits with soft, circular, brown, watery lesions with characteristic abundant whitish mycelium covering the surface of the colonized fruit were obtained from bins from a commercial storage facility located in Pennsylvania. Several samples were collected and prepared for pathogen isolation. Apples were rinsed with sterile water, and the lesions were sprayed with 70% ethanol until runoff. The apple skin was aseptically removed with a scalpel, and asymptomatic tissue was placed onto full strength potato dextrose agar (PDA) petri plates without antibiotics and incubated at 25°C under natural light. Two single-spore isolates were propagated on PDA and permanent cultures were maintained as slants and stored in a cold room at 4°C in the dark. Fungal colonies initially formed abundant fluffy white mycelium and produced a golden orange pigment on PDA at 25°C. Isolates were identified as Fusarium based on cultural and conidial morphology as macroconidia were slightly falcate, thin-walled, usually 3 to 5 septate, with a tapering apical cell that was on average 23.6 μm long × 5.0 μm wide (n = 50). Microconidia were produced on PDA plates while chlamydospores were not evident. Identity of the isolates was confirmed through DNA extraction followed by amplification and sequencing of the translation elongation factor (EF-1α, 350 bp) gene region. The amplicons were sequenced using the forward and reverse primers and assembled into a consensus representing 2X coverage. MegaBLAST analysis revealed that both isolates were 100% identical with many other culture collection F. avenaceum sequences in Genbank (Accessions JQ949291.1, JQ949305.1, and JQ949283.1), which confirms their identification in conjunction with the morphological observations. Koch's postulates were conducted to determine pathogenicity using organic ‘Gala’ apple fruit that were surface sanitized with soap and water, sprayed with 70% ethanol, and wiped dry. The fruit were wounded with a finishing nail to 3 mm depth, inoculated with 50 μl of a conidial suspension (1 × 104 conidia/ml) using a hemocytometer, and stored at 25°C in 80-count boxes on paper trays for 21 days. Water-only controls were symptomless. Ten fruit composed a replicate for each isolate, and the experiment was repeated. Symptoms observed on artificially inoculated ‘Gala’ apple fruit were identical to the decay observed on ‘Gala’ apples that were obtained from cold storage. Decay caused by F. avenaceum may represent an emerging problem for the apple storage and processing industry. Therefore, it is important to monitor for this pathogen to prevent future losses and mycotoxin contamination of processed fruit products caused by this fungus. To the best of our knowledge, this is the first report of Fusarium rot caused by F. avenaceum on apple fruit from cold storage in the United States. References: (1) Z. Sever et al. Arch. Ind. Hygiene Toxicol. 63:463, 2012. (2) J. L. Sorenson. J. Agric. Food Chem. 57:1632, 2009.

Download Full-text

The Anti-Jewish Narrative

Philosophia ◽

10.1007/s11406-021-00322-w ◽

2021 ◽

Author(s):

Nathan Cofnas

Keyword(s):

United States ◽

Jewish Identity ◽

Cultural Practices ◽

The United States ◽

Recent History ◽

High Intelligence ◽

Liberal Multiculturalism ◽

Anti Jewish ◽

Intellectual Movements

AbstractAccording to the mainstream narrative about race, all groups have the same innate dispositions and potential, and all disparities—at least those favoring whites—are due to past or present racism. Some people who reject this narrative gravitate toward an alternative, anti-Jewish narrative, which sees recent history in terms of a Jewish/gentile conflict. The most sophisticated promoter of the anti-Jewish narrative is the evolutionary psychologist Kevin MacDonald. MacDonald argues that Jews have a suite of genetic adaptations—including high intelligence and ethnocentrism—and cultural practices that lead them to undermine gentile society to advance their own evolutionary interests. He says that Jewish-designed intellectual movements have weakened gentile identity and culture while preserving Jewish identity and separatism. Cofnas recently argued that MacDonald’s theory is based on “systematically misrepresented sources and cherry-picked facts.” However, Cofnas gave short shrift to at least three key claims: (a) Jews are highly ethnocentric, (b) liberal Jews hypocritically advocate liberal multiculturalism for gentiles/gentile countries but racial purity and separatism for Jews/Israel, and (c) Jews are responsible for liberalism and mass immigration to the United States. The present paper examines these claims and concludes that MacDonald’s views are not supported.

Download Full-text

First Report of Pathogenicity of Fusarium sporotrichioides and Fusarium acuminatum on Sunflowers in the United States

Plant Health Progress ◽

10.1094/php-2010-0915-02-br ◽

2010 ◽

Vol 11 (1) ◽

pp. 42 ◽

Cited By ~ 4

Author(s):

F. Mathew ◽

B. Kirkeide ◽

T. Gulya ◽

S. Markell

Keyword(s):

United States ◽

Helianthus Annuus ◽

The United States ◽

Fusarium Sporotrichioides ◽

Charcoal Rot ◽

Koch’S Postulates ◽

First Report ◽

Fusarium Acuminatum ◽

Helianthus Annuus L ◽

Koch's Postulates

Widespread infection of charcoal rot was observed in a commercial sunflower field in Minnesota in September 2009. Based on morphology, isolates were identified as F. sporotrichioides and F. acuminatum. Koch's postulates demonstrated pathogencity of both species. To our knowledge, this is the first report of F. sporotrichoides and F. acuminatum causing disease on Helianthus annuus L. in the United States. Accepted for publication 23 August 2010. Published 15 September 2010.

Download Full-text

Converging cultures of communication: A comparative study of Internet use in China, Europe, and the United States

New Media & Society ◽

10.1177/14614448211015977 ◽

2021 ◽

Vol 23 (7) ◽

pp. 1751-1772

Author(s):

Jacob Ørmen ◽

Rasmus Helles ◽

Klaus Bruhn Jensen

Keyword(s):

United States ◽

Comparative Study ◽

Interpersonal Communication ◽

Internet Use ◽

Cultural Practices ◽

The United States ◽

Human Communication ◽

Shared Reality ◽

Cultural Research ◽

Media Systems

Global Internet use is circumscribed by local political and economic institutions and inscribed in distinctive cultural practices. This article presents a comparative study of Internet use in China, the United States, and five European countries. The empirical findings suggest a convergence of cultures, specifically regarding interpersonal communication, alongside characteristic national and sociodemographic configurations of different prototypes of human communication. Drawing on the classic understanding of communication as a cultural process producing, maintaining, repairing, and transforming a shared reality, we interpret such configurations as cultures of communication, which can be seen to differ, overlap, and converge across regions in distinctive ways. Looking beyond traditional media systems, we call for further cross-cultural research on the Internet as a generic communication system joining global and local forms of interaction.

Download Full-text